var raster = new ol.layer.Tile({
  source: new ol.source.MapQuest({layer: 'sat'})
});

var ol2d = new ol.Map({
  layers: [
raster
//    new ol.layer.Tile({
//      source: new ol.source.OSM()
//    })
  ],
  controls: ol.control.defaults({
    attributionOptions: /** @type {olx.control.AttributionOptions} */ ({
      collapsible: false
    })
  }),
  target: 'map',
  view: new ol.View({
    center: ol.proj.transform([25, 20], 'EPSG:4326', 'EPSG:3857'),
    zoom: 3
  })
});

var ol3d = new olcs.OLCesium({map: ol2d});
var scene = ol3d.getCesiumScene();
var terrainProvider = new Cesium.CesiumTerrainProvider({
    url : '//assets.agi.com/stk-terrain/world'
});
scene.terrainProvider = terrainProvider;

